net/mac80211/key.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007-2008  Johannes Berg <johannes@sipsolutions.net>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  * Copyright 2015-2017  Intel Deutschland GmbH
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/if_ether.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/list.h>
  17 #include <linux/rcupdate.h>
  18 #include <linux/rtnetlink.h>
  19 #include <linux/slab.h>
  20 #include <linux/export.h>
  21 #include <net/mac80211.h>
  22 #include <crypto/algapi.h>
  23 #include <asm/unaligned.h>
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "debugfs_key.h"
  27 #include "aes_ccm.h"
  28 #include "aes_cmac.h"
  29 #include "aes_gmac.h"
  30 #include "aes_gcm.h"
  31
  32
  33 /**
  34  * DOC: Key handling basics
  35  *
  36  * Key handling in mac80211 is done based on per-interface (sub_if_data)
  37  * keys and per-station keys. Since each station belongs to an interface,
  38  * each station key also belongs to that interface.
  39  *
  40  * Hardware acceleration is done on a best-effort basis for algorithms
  41  * that are implemented in software,  for each key the hardware is asked
  42  * to enable that key for offloading but if it cannot do that the key is
  43  * simply kept for software encryption (unless it is for an algorithm
  44  * that isn't implemented in software).
  45  * There is currently no way of knowing whether a key is handled in SW
  46  * or HW except by looking into debugfs.
  47  *
  48  * All key management is internally protected by a mutex. Within all
  49  * other parts of mac80211, key references are, just as STA structure
  50  * references, protected by RCU. Note, however, that some things are
  51  * unprotected, namely the key->sta dereferences within the hardware
  52  * acceleration functions. This means that sta_info_destroy() must
  53  * remove the key which waits for an RCU grace period.
  54  */
  55
  56 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
  57
  58 static void assert_key_lock(struct ieee80211_local *local)
  59 {
  60         lockdep_assert_held(&local->key_mtx);
  61 }
  62
  63 static void
  64 update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
  65 {
  66         struct ieee80211_sub_if_data *vlan;
  67
  68         if (sdata->vif.type != NL80211_IFTYPE_AP)
  69                 return;
  70
  71         /* crypto_tx_tailroom_needed_cnt is protected by this */
  72         assert_key_lock(sdata->local);
  73
  74         rcu_read_lock();
  75
  76         list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
  77                 vlan->crypto_tx_tailroom_needed_cnt += delta;
  78
  79         rcu_read_unlock();
  80 }
  81
  82 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
  83 {
  84         /*
  85          * When this count is zero, SKB resizing for allocating tailroom
  86          * for IV or MMIC is skipped. But, this check has created two race
  87          * cases in xmit path while transiting from zero count to one:
  88          *
  89          * 1. SKB resize was skipped because no key was added but just before
  90          * the xmit key is added and SW encryption kicks off.
  91          *
  92          * 2. SKB resize was skipped because all the keys were hw planted but
  93          * just before xmit one of the key is deleted and SW encryption kicks
  94          * off.
  95          *
  96          * In both the above case SW encryption will find not enough space for
  97          * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
  98          *
  99          * Solution has been explained at
 100          * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
 101          */
 102
 103         assert_key_lock(sdata->local);
 104
 105         update_vlan_tailroom_need_count(sdata, 1);
 106
 107         if (!sdata->crypto_tx_tailroom_needed_cnt++) {
 108                 /*
 109                  * Flush all XMIT packets currently using HW encryption or no
 110                  * encryption at all if the count transition is from 0 -> 1.
 111                  */
 112                 synchronize_net();
 113         }
 114 }
 115
 116 static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
 117                                          int delta)
 118 {
 119         assert_key_lock(sdata->local);
 120
 121         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
 122
 123         update_vlan_tailroom_need_count(sdata, -delta);
 124         sdata->crypto_tx_tailroom_needed_cnt -= delta;
 125 }
 126
 127 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
 128 {
 129         struct ieee80211_sub_if_data *sdata;
 130         struct sta_info *sta;
 131         int ret = -EOPNOTSUPP;
 132
 133         might_sleep();
 134
 135         if (key->flags & KEY_FLAG_TAINTED) {
 136                 /* If we get here, it's during resume and the key is
 137                  * tainted so shouldn't be used/programmed any more.
 138                  * However, its flags may still indicate that it was
 139                  * programmed into the device (since we're in resume)
 140                  * so clear that flag now to avoid trying to remove
 141                  * it again later.
 142                  */
 143                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 144                 return -EINVAL;
 145         }
 146
 147         if (!key->local->ops->set_key)
 148                 goto out_unsupported;
 149
 150         assert_key_lock(key->local);
 151
 152         sta = key->sta;
 153
 154         /*
 155          * If this is a per-STA GTK, check if it
 156          * is supported; if not, return.
 157          */
 158         if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
 159             !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))
 160                 goto out_unsupported;
 161
 162         if (sta && !sta->uploaded)
 163                 goto out_unsupported;
 164
 165         sdata = key->sdata;
 166         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 167                 /*
 168                  * The driver doesn't know anything about VLAN interfaces.
 169                  * Hence, don't send GTKs for VLAN interfaces to the driver.
 170                  */
 171                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
 172                         goto out_unsupported;
 173         }
 174
 175         ret = drv_set_key(key->local, SET_KEY, sdata,
 176                           sta ? &sta->sta : NULL, &key->conf);
 177
 178         if (!ret) {
 179                 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
 180
 181                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 182                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 183                         decrease_tailroom_need_count(sdata, 1);
 184
 185                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 186                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 187
 188                 return 0;
 189         }
 190
 191         if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
 192                 sdata_err(sdata,
 193                           "failed to set key (%d, %pM) to hardware (%d)\n",
 194                           key->conf.keyidx,
 195                           sta ? sta->sta.addr : bcast_addr, ret);
 196
 197  out_unsupported:
 198         switch (key->conf.cipher) {
 199         case WLAN_CIPHER_SUITE_WEP40:
 200         case WLAN_CIPHER_SUITE_WEP104:
 201         case WLAN_CIPHER_SUITE_TKIP:
 202         case WLAN_CIPHER_SUITE_CCMP:
 203         case WLAN_CIPHER_SUITE_CCMP_256:
 204         case WLAN_CIPHER_SUITE_AES_CMAC:
 205         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 206         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 207         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 208         case WLAN_CIPHER_SUITE_GCMP:
 209         case WLAN_CIPHER_SUITE_GCMP_256:
 210                 /* all of these we can do in software - if driver can */
 211                 if (ret == 1)
 212                         return 0;
 213                 if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
 214                         return -EINVAL;
 215                 return 0;
 216         default:
 217                 return -EINVAL;
 218         }
 219 }
 220
 221 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 222 {
 223         struct ieee80211_sub_if_data *sdata;
 224         struct sta_info *sta;
 225         int ret;
 226
 227         might_sleep();
 228
 229         if (!key || !key->local->ops->set_key)
 230                 return;
 231
 232         assert_key_lock(key->local);
 233
 234         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 235                 return;
 236
 237         sta = key->sta;
 238         sdata = key->sdata;
 239
 240         if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 241               (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 242                 increment_tailroom_need_count(sdata);
 243
 244         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 245                           sta ? &sta->sta : NULL, &key->conf);
 246
 247         if (ret)
 248                 sdata_err(sdata,
 249                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 250                           key->conf.keyidx,
 251                           sta ? sta->sta.addr : bcast_addr, ret);
 252
 253         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 254 }
 255
 256 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 257                                         int idx, bool uni, bool multi)
 258 {
 259         struct ieee80211_key *key = NULL;
 260
 261         assert_key_lock(sdata->local);
 262
 263         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 264                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 265
 266         if (uni) {
 267                 rcu_assign_pointer(sdata->default_unicast_key, key);
 268                 ieee80211_check_fast_xmit_iface(sdata);
 269                 drv_set_default_unicast_key(sdata->local, sdata, idx);
 270         }
 271
 272         if (multi)
 273                 rcu_assign_pointer(sdata->default_multicast_key, key);
 274
 275         ieee80211_debugfs_key_update_default(sdata);
 276 }
 277
 278 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 279                                bool uni, bool multi)
 280 {
 281         mutex_lock(&sdata->local->key_mtx);
 282         __ieee80211_set_default_key(sdata, idx, uni, multi);
 283         mutex_unlock(&sdata->local->key_mtx);
 284 }
 285
 286 static void
 287 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 288 {
 289         struct ieee80211_key *key = NULL;
 290
 291         assert_key_lock(sdata->local);
 292
 293         if (idx >= NUM_DEFAULT_KEYS &&
 294             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 295                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 296
 297         rcu_assign_pointer(sdata->default_mgmt_key, key);
 298
 299         ieee80211_debugfs_key_update_default(sdata);
 300 }
 301
 302 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 303                                     int idx)
 304 {
 305         mutex_lock(&sdata->local->key_mtx);
 306         __ieee80211_set_default_mgmt_key(sdata, idx);
 307         mutex_unlock(&sdata->local->key_mtx);
 308 }
 309
 310
 311 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 312                                   struct sta_info *sta,
 313                                   bool pairwise,
 314                                   struct ieee80211_key *old,
 315                                   struct ieee80211_key *new)
 316 {
 317         int idx;
 318         bool defunikey, defmultikey, defmgmtkey;
 319
 320         /* caller must provide at least one old/new */
 321         if (WARN_ON(!new && !old))
 322                 return;
 323
 324         if (new)
 325                 list_add_tail_rcu(&new->list, &sdata->key_list);
 326
 327         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 328
 329         if (old)
 330                 idx = old->conf.keyidx;
 331         else
 332                 idx = new->conf.keyidx;
 333
 334         if (sta) {
 335                 if (pairwise) {
 336                         rcu_assign_pointer(sta->ptk[idx], new);
 337                         sta->ptk_idx = idx;
 338                         ieee80211_check_fast_xmit(sta);
 339                 } else {
 340                         rcu_assign_pointer(sta->gtk[idx], new);
 341                 }
 342                 ieee80211_check_fast_rx(sta);
 343         } else {
 344                 defunikey = old &&
 345                         old == key_mtx_dereference(sdata->local,
 346                                                 sdata->default_unicast_key);
 347                 defmultikey = old &&
 348                         old == key_mtx_dereference(sdata->local,
 349                                                 sdata->default_multicast_key);
 350                 defmgmtkey = old &&
 351                         old == key_mtx_dereference(sdata->local,
 352                                                 sdata->default_mgmt_key);
 353
 354                 if (defunikey && !new)
 355                         __ieee80211_set_default_key(sdata, -1, true, false);
 356                 if (defmultikey && !new)
 357                         __ieee80211_set_default_key(sdata, -1, false, true);
 358                 if (defmgmtkey && !new)
 359                         __ieee80211_set_default_mgmt_key(sdata, -1);
 360
 361                 rcu_assign_pointer(sdata->keys[idx], new);
 362                 if (defunikey && new)
 363                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 364                                                     true, false);
 365                 if (defmultikey && new)
 366                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 367                                                     false, true);
 368                 if (defmgmtkey && new)
 369                         __ieee80211_set_default_mgmt_key(sdata,
 370                                                          new->conf.keyidx);
 371         }
 372
 373         if (old)
 374                 list_del_rcu(&old->list);
 375 }
 376
 377 struct ieee80211_key *
 378 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 379                     const u8 *key_data,
 380                     size_t seq_len, const u8 *seq,
 381                     const struct ieee80211_cipher_scheme *cs)
 382 {
 383         struct ieee80211_key *key;
 384         int i, j, err;
 385
 386         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 387                 return ERR_PTR(-EINVAL);
 388
 389         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 390         if (!key)
 391                 return ERR_PTR(-ENOMEM);
 392
 393         /*
 394          * Default to software encryption; we'll later upload the
 395          * key to the hardware if possible.
 396          */
 397         key->conf.flags = 0;
 398         key->flags = 0;
 399
 400         key->conf.cipher = cipher;
 401         key->conf.keyidx = idx;
 402         key->conf.keylen = key_len;
 403         switch (cipher) {
 404         case WLAN_CIPHER_SUITE_WEP40:
 405         case WLAN_CIPHER_SUITE_WEP104:
 406                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 407                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 408                 break;
 409         case WLAN_CIPHER_SUITE_TKIP:
 410                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 411                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 412                 if (seq) {
 413                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 414                                 key->u.tkip.rx[i].iv32 =
 415                                         get_unaligned_le32(&seq[2]);
 416                                 key->u.tkip.rx[i].iv16 =
 417                                         get_unaligned_le16(seq);
 418                         }
 419                 }
 420                 spin_lock_init(&key->u.tkip.txlock);
 421                 break;
 422         case WLAN_CIPHER_SUITE_CCMP:
 423                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 424                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 425                 if (seq) {
 426                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 427                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 428                                         key->u.ccmp.rx_pn[i][j] =
 429                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 430                 }
 431                 /*
 432                  * Initialize AES key state here as an optimization so that
 433                  * it does not need to be initialized for every packet.
 434                  */
 435                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 436                         key_data, key_len, IEEE80211_CCMP_MIC_LEN);
 437                 if (IS_ERR(key->u.ccmp.tfm)) {
 438                         err = PTR_ERR(key->u.ccmp.tfm);
 439                         kfree(key);
 440                         return ERR_PTR(err);
 441                 }
 442                 break;
 443         case WLAN_CIPHER_SUITE_CCMP_256:
 444                 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
 445                 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
 446                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 447                         for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
 448                                 key->u.ccmp.rx_pn[i][j] =
 449                                         seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
 450                 /* Initialize AES key state here as an optimization so that
 451                  * it does not need to be initialized for every packet.
 452                  */
 453                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 454                         key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
 455                 if (IS_ERR(key->u.ccmp.tfm)) {
 456                         err = PTR_ERR(key->u.ccmp.tfm);
 457                         kfree(key);
 458                         return ERR_PTR(err);
 459                 }
 460                 break;
 461         case WLAN_CIPHER_SUITE_AES_CMAC:
 462         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 463                 key->conf.iv_len = 0;
 464                 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 465                         key->conf.icv_len = sizeof(struct ieee80211_mmie);
 466                 else
 467                         key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 468                 if (seq)
 469                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 470                                 key->u.aes_cmac.rx_pn[j] =
 471                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 472                 /*
 473                  * Initialize AES key state here as an optimization so that
 474                  * it does not need to be initialized for every packet.
 475                  */
 476                 key->u.aes_cmac.tfm =
 477                         ieee80211_aes_cmac_key_setup(key_data, key_len);
 478                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 479                         err = PTR_ERR(key->u.aes_cmac.tfm);
 480                         kfree(key);
 481                         return ERR_PTR(err);
 482                 }
 483                 break;
 484         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 485         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 486                 key->conf.iv_len = 0;
 487                 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 488                 if (seq)
 489                         for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
 490                                 key->u.aes_gmac.rx_pn[j] =
 491                                         seq[IEEE80211_GMAC_PN_LEN - j - 1];
 492                 /* Initialize AES key state here as an optimization so that
 493                  * it does not need to be initialized for every packet.
 494                  */
 495                 key->u.aes_gmac.tfm =
 496                         ieee80211_aes_gmac_key_setup(key_data, key_len);
 497                 if (IS_ERR(key->u.aes_gmac.tfm)) {
 498                         err = PTR_ERR(key->u.aes_gmac.tfm);
 499                         kfree(key);
 500                         return ERR_PTR(err);
 501                 }
 502                 break;
 503         case WLAN_CIPHER_SUITE_GCMP:
 504         case WLAN_CIPHER_SUITE_GCMP_256:
 505                 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
 506                 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
 507                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 508                         for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
 509                                 key->u.gcmp.rx_pn[i][j] =
 510                                         seq[IEEE80211_GCMP_PN_LEN - j - 1];
 511                 /* Initialize AES key state here as an optimization so that
 512                  * it does not need to be initialized for every packet.
 513                  */
 514                 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
 515                                                                       key_len);
 516                 if (IS_ERR(key->u.gcmp.tfm)) {
 517                         err = PTR_ERR(key->u.gcmp.tfm);
 518                         kfree(key);
 519                         return ERR_PTR(err);
 520                 }
 521                 break;
 522         default:
 523                 if (cs) {
 524                         if (seq_len && seq_len != cs->pn_len) {
 525                                 kfree(key);
 526                                 return ERR_PTR(-EINVAL);
 527                         }
 528
 529                         key->conf.iv_len = cs->hdr_len;
 530                         key->conf.icv_len = cs->mic_len;
 531                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 532                                 for (j = 0; j < seq_len; j++)
 533                                         key->u.gen.rx_pn[i][j] =
 534                                                         seq[seq_len - j - 1];
 535                         key->flags |= KEY_FLAG_CIPHER_SCHEME;
 536                 }
 537         }
 538         memcpy(key->conf.key, key_data, key_len);
 539         INIT_LIST_HEAD(&key->list);
 540
 541         return key;
 542 }
 543
 544 static void ieee80211_key_free_common(struct ieee80211_key *key)
 545 {
 546         switch (key->conf.cipher) {
 547         case WLAN_CIPHER_SUITE_CCMP:
 548         case WLAN_CIPHER_SUITE_CCMP_256:
 549                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 550                 break;
 551         case WLAN_CIPHER_SUITE_AES_CMAC:
 552         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 553                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 554                 break;
 555         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 556         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 557                 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
 558                 break;
 559         case WLAN_CIPHER_SUITE_GCMP:
 560         case WLAN_CIPHER_SUITE_GCMP_256:
 561                 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
 562                 break;
 563         }
 564         kzfree(key);
 565 }
 566
 567 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 568                                     bool delay_tailroom)
 569 {
 570         if (key->local)
 571                 ieee80211_key_disable_hw_accel(key);
 572
 573         if (key->local) {
 574                 struct ieee80211_sub_if_data *sdata = key->sdata;
 575
 576                 ieee80211_debugfs_key_remove(key);
 577
 578                 if (delay_tailroom) {
 579                         /* see ieee80211_delayed_tailroom_dec */
 580                         sdata->crypto_tx_tailroom_pending_dec++;
 581                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 582                                               HZ/2);
 583                 } else {
 584                         decrease_tailroom_need_count(sdata, 1);
 585                 }
 586         }
 587
 588         ieee80211_key_free_common(key);
 589 }
 590
 591 static void ieee80211_key_destroy(struct ieee80211_key *key,
 592                                   bool delay_tailroom)
 593 {
 594         if (!key)
 595                 return;
 596
 597         /*
 598          * Synchronize so the TX path and rcu key iterators
 599          * can no longer be using this key before we free/remove it.
 600          */
 601         synchronize_net();
 602
 603         __ieee80211_key_destroy(key, delay_tailroom);
 604 }
 605
 606 void ieee80211_key_free_unused(struct ieee80211_key *key)
 607 {
 608         WARN_ON(key->sdata || key->local);
 609         ieee80211_key_free_common(key);
 610 }
 611
 612 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
 613                                     struct ieee80211_key *old,
 614                                     struct ieee80211_key *new)
 615 {
 616         u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
 617         u8 *tk_old, *tk_new;
 618
 619         if (!old || new->conf.keylen != old->conf.keylen)
 620                 return false;
 621
 622         tk_old = old->conf.key;
 623         tk_new = new->conf.key;
 624
 625         /*
 626          * In station mode, don't compare the TX MIC key, as it's never used
 627          * and offloaded rekeying may not care to send it to the host. This
 628          * is the case in iwlwifi, for example.
 629          */
 630         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 631             new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
 632             new->conf.keylen == WLAN_KEY_LEN_TKIP &&
 633             !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
 634                 memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
 635                 memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
 636                 memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
 637                 memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
 638                 tk_old = tkip_old;
 639                 tk_new = tkip_new;
 640         }
 641
 642         return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
 643 }
 644
 645 int ieee80211_key_link(struct ieee80211_key *key,
 646                        struct ieee80211_sub_if_data *sdata,
 647                        struct sta_info *sta)
 648 {
 649         struct ieee80211_local *local = sdata->local;
 650         struct ieee80211_key *old_key;
 651         int idx = key->conf.keyidx;
 652         bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 653         /*
 654          * We want to delay tailroom updates only for station - in that
 655          * case it helps roaming speed, but in other cases it hurts and
 656          * can cause warnings to appear.
 657          */
 658         bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;
 659         int ret;
 660
 661         mutex_lock(&sdata->local->key_mtx);
 662
 663         if (sta && pairwise)
 664                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 665         else if (sta)
 666                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 667         else
 668                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 669
 670         /*
 671          * Silently accept key re-installation without really installing the
 672          * new version of the key to avoid nonce reuse or replay issues.
 673          */
 674         if (ieee80211_key_identical(sdata, old_key, key)) {
 675                 ieee80211_key_free_unused(key);
 676                 ret = 0;
 677                 goto out;
 678         }
 679
 680         key->local = sdata->local;
 681         key->sdata = sdata;
 682         key->sta = sta;
 683
 684         increment_tailroom_need_count(sdata);
 685
 686         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 687         ieee80211_key_destroy(old_key, delay_tailroom);
 688
 689         ieee80211_debugfs_key_add(key);
 690
 691         if (!local->wowlan) {
 692                 ret = ieee80211_key_enable_hw_accel(key);
 693                 if (ret)
 694                         ieee80211_key_free(key, delay_tailroom);
 695         } else {
 696                 ret = 0;
 697         }
 698
 699  out:
 700         mutex_unlock(&sdata->local->key_mtx);
 701
 702         return ret;
 703 }
 704
 705 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 706 {
 707         if (!key)
 708                 return;
 709
 710         /*
 711          * Replace key with nothingness if it was ever used.
 712          */
 713         if (key->sdata)
 714                 ieee80211_key_replace(key->sdata, key->sta,
 715                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 716                                 key, NULL);
 717         ieee80211_key_destroy(key, delay_tailroom);
 718 }
 719
 720 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 721 {
 722         struct ieee80211_key *key;
 723         struct ieee80211_sub_if_data *vlan;
 724
 725         ASSERT_RTNL();
 726
 727         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 728                 return;
 729
 730         mutex_lock(&sdata->local->key_mtx);
 731
 732         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 733                      sdata->crypto_tx_tailroom_pending_dec);
 734
 735         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 736                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 737                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 738                                      vlan->crypto_tx_tailroom_pending_dec);
 739         }
 740
 741         list_for_each_entry(key, &sdata->key_list, list) {
 742                 increment_tailroom_need_count(sdata);
 743                 ieee80211_key_enable_hw_accel(key);
 744         }
 745
 746         mutex_unlock(&sdata->local->key_mtx);
 747 }
 748
 749 void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
 750 {
 751         struct ieee80211_sub_if_data *vlan;
 752
 753         mutex_lock(&sdata->local->key_mtx);
 754
 755         sdata->crypto_tx_tailroom_needed_cnt = 0;
 756
 757         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 758                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 759                         vlan->crypto_tx_tailroom_needed_cnt = 0;
 760         }
 761
 762         mutex_unlock(&sdata->local->key_mtx);
 763 }
 764
 765 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 766                          struct ieee80211_vif *vif,
 767                          void (*iter)(struct ieee80211_hw *hw,
 768                                       struct ieee80211_vif *vif,
 769                                       struct ieee80211_sta *sta,
 770                                       struct ieee80211_key_conf *key,
 771                                       void *data),
 772                          void *iter_data)
 773 {
 774         struct ieee80211_local *local = hw_to_local(hw);
 775         struct ieee80211_key *key, *tmp;
 776         struct ieee80211_sub_if_data *sdata;
 777
 778         ASSERT_RTNL();
 779
 780         mutex_lock(&local->key_mtx);
 781         if (vif) {
 782                 sdata = vif_to_sdata(vif);
 783                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 784                         iter(hw, &sdata->vif,
 785                              key->sta ? &key->sta->sta : NULL,
 786                              &key->conf, iter_data);
 787         } else {
 788                 list_for_each_entry(sdata, &local->interfaces, list)
 789                         list_for_each_entry_safe(key, tmp,
 790                                                  &sdata->key_list, list)
 791                                 iter(hw, &sdata->vif,
 792                                      key->sta ? &key->sta->sta : NULL,
 793                                      &key->conf, iter_data);
 794         }
 795         mutex_unlock(&local->key_mtx);
 796 }
 797 EXPORT_SYMBOL(ieee80211_iter_keys);
 798
 799 static void
 800 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
 801                          struct ieee80211_sub_if_data *sdata,
 802                          void (*iter)(struct ieee80211_hw *hw,
 803                                       struct ieee80211_vif *vif,
 804                                       struct ieee80211_sta *sta,
 805                                       struct ieee80211_key_conf *key,
 806                                       void *data),
 807                          void *iter_data)
 808 {
 809         struct ieee80211_key *key;
 810
 811         list_for_each_entry_rcu(key, &sdata->key_list, list) {
 812                 /* skip keys of station in removal process */
 813                 if (key->sta && key->sta->removed)
 814                         continue;
 815                 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 816                         continue;
 817
 818                 iter(hw, &sdata->vif,
 819                      key->sta ? &key->sta->sta : NULL,
 820                      &key->conf, iter_data);
 821         }
 822 }
 823
 824 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
 825                              struct ieee80211_vif *vif,
 826                              void (*iter)(struct ieee80211_hw *hw,
 827                                           struct ieee80211_vif *vif,
 828                                           struct ieee80211_sta *sta,
 829                                           struct ieee80211_key_conf *key,
 830                                           void *data),
 831                              void *iter_data)
 832 {
 833         struct ieee80211_local *local = hw_to_local(hw);
 834         struct ieee80211_sub_if_data *sdata;
 835
 836         if (vif) {
 837                 sdata = vif_to_sdata(vif);
 838                 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
 839         } else {
 840                 list_for_each_entry_rcu(sdata, &local->interfaces, list)
 841                         _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
 842         }
 843 }
 844 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
 845
 846 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 847                                       struct list_head *keys)
 848 {
 849         struct ieee80211_key *key, *tmp;
 850
 851         decrease_tailroom_need_count(sdata,
 852                                      sdata->crypto_tx_tailroom_pending_dec);
 853         sdata->crypto_tx_tailroom_pending_dec = 0;
 854
 855         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 856
 857         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 858                 ieee80211_key_replace(key->sdata, key->sta,
 859                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 860                                 key, NULL);
 861                 list_add_tail(&key->list, keys);
 862         }
 863
 864         ieee80211_debugfs_key_update_default(sdata);
 865 }
 866
 867 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 868                          bool force_synchronize)
 869 {
 870         struct ieee80211_local *local = sdata->local;
 871         struct ieee80211_sub_if_data *vlan;
 872         struct ieee80211_sub_if_data *master;
 873         struct ieee80211_key *key, *tmp;
 874         LIST_HEAD(keys);
 875
 876         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 877
 878         mutex_lock(&local->key_mtx);
 879
 880         ieee80211_free_keys_iface(sdata, &keys);
 881
 882         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 883                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 884                         ieee80211_free_keys_iface(vlan, &keys);
 885         }
 886
 887         if (!list_empty(&keys) || force_synchronize)
 888                 synchronize_net();
 889         list_for_each_entry_safe(key, tmp, &keys, list)
 890                 __ieee80211_key_destroy(key, false);
 891
 892         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 893                 if (sdata->bss) {
 894                         master = container_of(sdata->bss,
 895                                               struct ieee80211_sub_if_data,
 896                                               u.ap);
 897
 898                         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
 899                                      master->crypto_tx_tailroom_needed_cnt);
 900                 }
 901         } else {
 902                 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 903                              sdata->crypto_tx_tailroom_pending_dec);
 904         }
 905
 906         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 907                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 908                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 909                                      vlan->crypto_tx_tailroom_pending_dec);
 910         }
 911
 912         mutex_unlock(&local->key_mtx);
 913 }
 914
 915 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 916                              struct sta_info *sta)
 917 {
 918         struct ieee80211_key *key;
 919         int i;
 920
 921         mutex_lock(&local->key_mtx);
 922         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 923                 key = key_mtx_dereference(local, sta->gtk[i]);
 924                 if (!key)
 925                         continue;
 926                 ieee80211_key_replace(key->sdata, key->sta,
 927                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 928                                 key, NULL);
 929                 __ieee80211_key_destroy(key, key->sdata->vif.type ==
 930                                         NL80211_IFTYPE_STATION);
 931         }
 932
 933         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 934                 key = key_mtx_dereference(local, sta->ptk[i]);
 935                 if (!key)
 936                         continue;
 937                 ieee80211_key_replace(key->sdata, key->sta,
 938                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 939                                 key, NULL);
 940                 __ieee80211_key_destroy(key, key->sdata->vif.type ==
 941                                         NL80211_IFTYPE_STATION);
 942         }
 943
 944         mutex_unlock(&local->key_mtx);
 945 }
 946
 947 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 948 {
 949         struct ieee80211_sub_if_data *sdata;
 950
 951         sdata = container_of(wk, struct ieee80211_sub_if_data,
 952                              dec_tailroom_needed_wk.work);
 953
 954         /*
 955          * The reason for the delayed tailroom needed decrementing is to
 956          * make roaming faster: during roaming, all keys are first deleted
 957          * and then new keys are installed. The first new key causes the
 958          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 959          * the cost of synchronize_net() (which can be slow). Avoid this
 960          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 961          * key removal for a while, so if we roam the value is larger than
 962          * zero and no 0->1 transition happens.
 963          *
 964          * The cost is that if the AP switching was from an AP with keys
 965          * to one without, we still allocate tailroom while it would no
 966          * longer be needed. However, in the typical (fast) roaming case
 967          * within an ESS this usually won't happen.
 968          */
 969
 970         mutex_lock(&sdata->local->key_mtx);
 971         decrease_tailroom_need_count(sdata,
 972                                      sdata->crypto_tx_tailroom_pending_dec);
 973         sdata->crypto_tx_tailroom_pending_dec = 0;
 974         mutex_unlock(&sdata->local->key_mtx);
 975 }
 976
 977 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 978                                 const u8 *replay_ctr, gfp_t gfp)
 979 {
 980         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 981
 982         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 983
 984         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 985 }
 986 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 987
 988 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 989                               int tid, struct ieee80211_key_seq *seq)
 990 {
 991         struct ieee80211_key *key;
 992         const u8 *pn;
 993
 994         key = container_of(keyconf, struct ieee80211_key, conf);
 995
 996         switch (key->conf.cipher) {
 997         case WLAN_CIPHER_SUITE_TKIP:
 998                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 999                         return;
1000                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1001                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
1002                 break;
1003         case WLAN_CIPHER_SUITE_CCMP:
1004         case WLAN_CIPHER_SUITE_CCMP_256:
1005                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1006                         return;
1007                 if (tid < 0)
1008                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1009                 else
1010                         pn = key->u.ccmp.rx_pn[tid];
1011                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
1012                 break;
1013         case WLAN_CIPHER_SUITE_AES_CMAC:
1014         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1015                 if (WARN_ON(tid != 0))
1016                         return;
1017                 pn = key->u.aes_cmac.rx_pn;
1018                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
1019                 break;
1020         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1021         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1022                 if (WARN_ON(tid != 0))
1023                         return;
1024                 pn = key->u.aes_gmac.rx_pn;
1025                 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
1026                 break;
1027         case WLAN_CIPHER_SUITE_GCMP:
1028         case WLAN_CIPHER_SUITE_GCMP_256:
1029                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1030                         return;
1031                 if (tid < 0)
1032                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1033                 else
1034                         pn = key->u.gcmp.rx_pn[tid];
1035                 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1036                 break;
1037         }
1038 }
1039 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1040
1041 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1042                               int tid, struct ieee80211_key_seq *seq)
1043 {
1044         struct ieee80211_key *key;
1045         u8 *pn;
1046
1047         key = container_of(keyconf, struct ieee80211_key, conf);
1048
1049         switch (key->conf.cipher) {
1050         case WLAN_CIPHER_SUITE_TKIP:
1051                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1052                         return;
1053                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1054                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1055                 break;
1056         case WLAN_CIPHER_SUITE_CCMP:
1057         case WLAN_CIPHER_SUITE_CCMP_256:
1058                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1059                         return;
1060                 if (tid < 0)
1061                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1062                 else
1063                         pn = key->u.ccmp.rx_pn[tid];
1064                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1065                 break;
1066         case WLAN_CIPHER_SUITE_AES_CMAC:
1067         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1068                 if (WARN_ON(tid != 0))
1069                         return;
1070                 pn = key->u.aes_cmac.rx_pn;
1071                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1072                 break;
1073         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1074         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1075                 if (WARN_ON(tid != 0))
1076                         return;
1077                 pn = key->u.aes_gmac.rx_pn;
1078                 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1079                 break;
1080         case WLAN_CIPHER_SUITE_GCMP:
1081         case WLAN_CIPHER_SUITE_GCMP_256:
1082                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1083                         return;
1084                 if (tid < 0)
1085                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1086                 else
1087                         pn = key->u.gcmp.rx_pn[tid];
1088                 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1089                 break;
1090         default:
1091                 WARN_ON(1);
1092                 break;
1093         }
1094 }
1095 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1096
1097 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1098 {
1099         struct ieee80211_key *key;
1100
1101         key = container_of(keyconf, struct ieee80211_key, conf);
1102
1103         assert_key_lock(key->local);
1104
1105         /*
1106          * if key was uploaded, we assume the driver will/has remove(d)
1107          * it, so adjust bookkeeping accordingly
1108          */
1109         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1110                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1111
1112                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
1113                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1114                         increment_tailroom_need_count(key->sdata);
1115         }
1116
1117         ieee80211_key_free(key, false);
1118 }
1119 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1120
1121 struct ieee80211_key_conf *
1122 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1123                         struct ieee80211_key_conf *keyconf)
1124 {
1125         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1126         struct ieee80211_local *local = sdata->local;
1127         struct ieee80211_key *key;
1128         int err;
1129
1130         if (WARN_ON(!local->wowlan))
1131                 return ERR_PTR(-EINVAL);
1132
1133         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1134                 return ERR_PTR(-EINVAL);
1135
1136         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1137                                   keyconf->keylen, keyconf->key,
1138                                   0, NULL, NULL);
1139         if (IS_ERR(key))
1140                 return ERR_CAST(key);
1141
1142         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1143                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1144
1145         err = ieee80211_key_link(key, sdata, NULL);
1146         if (err)
1147                 return ERR_PTR(err);
1148
1149         return &key->conf;
1150 }
1151 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);